Memristive devices, or memristors, are a new type of switching devices with an electrically switchable device resistance. Memristive devices are both scientifically and technically interesting, and hold promise for non-volatile memory (NVM) and other fields. As today's flash memory technology is reaching its scaling limit, there is an urgent need for new memory technologies that can meet the storage capacity and access speed demanded by future applications. Memories using resistive switching devices, such as memristors, are a promising candidate for meeting that need. For NVM applications, many memristive devices can be formed in a two-dimensional array to provide a very high storage capacity.